When you're trying to save money, it's often hard to figure out what expenses really matter to you. You might even spend more time rationalizing the expense than you would just buying it. To keep that from happening, financial blog Budgets are Sexy shares the "10 rule."

The "10 rule" is pretty straightforward, and its purpose is to help you make a solid decision about a purchase:

Anything you buy today, your future self is paying 10x as much for. So add a zero onto the price tag, and ask yourself if it's still worth it. If it is, buy it and enjoy it. If not, then forget it... According to the Ten Rule, if you buy a new car today for $20 grand, then your future self is paying $200 grand. That $800 computer is $8,000. The $50 dinner for two is $500. Karate lessons for $150/month are $1,500/month.

If that sounds a little absurd, you're right. But the point isn't necessarily to talk you out of every single purchase. The purpose of the 10 Rule is to teach you to really think about each purchase, and assess the value as it relates to you. It's an interesting approach, and if you find yourself buying a lot of useless stuff, it might be worth putting yourself in this mindset for a little while to train your brain. Head over to Budgets are Sexy for the full post.